Drawbridge



(No Model.) 3 Shets-Sheet 1. C. A. P. TURNER 8a P. A. WARNER.

'D RAWB RIDGE.

No. 503,273. Patented Aug. 15,` 1893.

AJ BJI 15's. 5.

(No Model.) 3 snets'sneen 2. C. A. P. TURNER sa P. A. WARNER.

y DRAWRRIDGR.

No. 503,273. I Pawnted Aug. 15, '1893.

3 Sheets-Sheet 3.

(No Model.)

C. A. P. TURNER 8v P. A'. WARNER.

DRAWBRIDGE. ige. '73.. "s PatentemAgelg 5, .1893.

el?? H UNITED STATES PATENT OFFICE.

CLAUDE A. P. TURNER, OF ASHTON, RHODE ISLAND, AND PHILIP A. VARNER, OFWEST NEWTON, MASSACHUSETTS.

DRAWBRIDGE.

SPECIFICATION forming part of Letters Patent No. 503,273, dated August15, 1893.

Application filed March '7, 1891.

To all whom it may concern.-

Beit known that we, CLAUDE A. P. TURNER, of Ashton, in the county ofProvidence and State of Rhode Island, and PHILIP A. WAR- NER, of WestNewton, in the county of Middlesex and State of Massachusetts, haveinvented certain new and useful Improvements in Drawbridges, of whichthe following, taken in connection with the accompanying drawings, is aspecification.

Our invention relates to draw-bridges, has for its object the productionof a convenient and ready means of raising and lowering the ends of thedrawbridge before and after opening and closing the saule, and itconsists in certain novel features of construction, arrangement andcombination of parts which will be readily understood by reference tothe description of the drawings and to the claims hereinafter given, andin which our invention is clearly pointed out.

Figures l, 2, 3, 4 and 5 of the drawings represent diagrams illustratingthe application of our invention to drawbridges in which six differentforms of trusses are employed. Fig. 6 is a side elevation of the centralportion of a drawbridge with our invention applied thereto. Fig. '.7 isan elevation of the transverse strut connecting the upper portions ofthe central frames or supports, portions of said. frames, and theshafting and gearing for operating the toggles to raise the ends ofthedrawbridge. Fig. S is a sectional elevation of the upper portions of thecentral frames or supports, the cutting plane of the left half of saidfigure being through the transverse strut on line .fr n: on Fig. 9. Fig.9 is a transverse sectional elevation of same, on line y, y, on Fig. 8.Fig. 10 is a partial horizontal section ot one of said supports on linez, a, on Fig. 8. Fig. ll is an elevation of a portion of the inner endof one of the toggle links, as formed for use in connection with acontinuous truss bridge, and Fig. l2 is a similar elevation of a portionof such link, as formed for use in connection with adiscontinuous trussbridge.

In carrying out ourinvention we introduce into the upper chord of eachof the bridge trusses, a toggle joint Vat the center of the bridge;sections of the upper chord themselves forming the toggle links, theinner ends of Serial No. 384,085. (No model.)

which are connected together and to a vertical screw eye bolt providedwith a nut, and suitable gearing and shafting for revolving the said nutwhereby the center of said chord may be raised thus causing the outerends of the bridge arms to be raised from their bearings on theabutments, as will be further described.

In the drawings, forming a part of this specification, A is theturn-table mounted upon a series of trucks a a arranged to roll upon anannular track plate d supported upon the central pier ZJ, in a wellknown manner.

B and B are two transverse girders or beams resting upon said turn-tableand connected together by the" longitudinal girders or central sectionsC of the stringers.

D and D are the end sections of the stringers, the inner ends of whichare supported by, but not rigidly connected to, the girders B andiBrespectively, said stringers extending therefrom to the abutmeuts or endsupports of the bridge.

D2, D2, are the lower chord sections of the trusses resting at theirinner ends upon the girders B, B.

E and E are the ends of the upper chords of the trusses which constituteparts of the two arms of the bridge which span the two channels.

F and F are the main diagonal struts, G are the vertical hangers and IIthe diagonal tension rods.

So far the bridge shown is of ordinary or Well known construction, andthe trusses forming the two arms of the bridge that span the channelswhen closed may be of any of the forms shown in Figs. l, 2, 3, 4, and 5or of any other well known form without affecting the principles of ourinvention.

At the center of the bridge, directly over the turntable A, we erect twotriangular struts I and I', one at each side of the bridge in line withthe trusses, and each composed of two pairs of standards c c inclinedtoward each other and connected together by suitable tie pieces d d ande and diagonal bars f f as shown, the "tops of said triangular struts Iand I being connected together by the transverse struts J, J, composedof upper and lower chords g and g and the diagonal lacing g2 as shown inFig. '7. The upper ends of the triangular struts I and I are covered bycap plates 71, having secured centrally thereon the circular plates orbosses h upon which are mounted so as to be revoluble thereon the nuts Kand K respectively which nuts are provided with suitable square femalethreads to iit corresponding male threads on the suspension eye bolts Land L', the lower ends of which are provided with eyes to receive thetoggle pins t' and t" respectively, the ends of which pins are flattenedon opposite sides and tit into vertical guidewaysj j formed by rivetingto the inner faces of the tie pieces d the platesj,j, as shown in Figs.8, 9, and l0. Each of the pins 'L' and i has fitted thereon one end ofeach of four toggle links or rods 7c k the opposite ends of which arepivoted two at Z and two at Z to the inner ends of the upper chord barsE and E respectively as.

shown in Fig. 6.

The nut K has formed thereon two sets of bevel gear teeth m and n withthe former of which the bevel pinion m secured upon the upper end of theinclined shaft o engages to impart to said nut K a rotary motion aboutthe screw suspension eye bolt L thus raising and lowering said screw eyebolt, and with it the inner ends of the toggle links k la. The shaft ois mounted in suitable bearings on one pair of the inclined standards cc of the triangular strut I, and is provided at its lower end withsuitable gearing for revolving it by hand as the bevel or miter gears o02 the short shaft o3 and the crank o4; or power may be applied to it inany other well known manner. A horizontal shaft p is mounted in suitablebearings secured upon the cap-plates h, and has secured upon one end thebevel gear wheel p which engages with and is driven by the gear teeth non the nut K, and also has secured upon its other end the bevel gearwheel p2 which engages with the bevel gear teeth n formed on the nut K',so as to revolve said nut about its screwr eye bolt L thus raising andlowering said eye bolt and with it the inner ends of the toggle links 2c7c on that side of the bridge. The screw bolt L and its nut K areprovided with right hand threads and the screw bolt L and its nut K areprovided with left hand threads or vice versa7 so that both eye boltswill be raised or lowered together, and the distance between the innerends of the upper chordv bars E and E will be increased or diminishedalike on both sides of the bridge.

When discontinuous trusses are used, thev eyes in the inner-ends of thetoggle links are slotted or made oblong as shown in Fig. l2 and indotted lines in Fig. 8, but when continuous trusses are employed theeyes in said links will be made to fit the toggle pin as shown in Fig.ll.

to render it impractical to open the draw until its ends are lifted soas to relieve the pressure on the abutments. To accomplish this, theshaft o is revolved, either by t-he hand gearing shown, or by steam orother power applied thereto in any well known manner, in such adirection as to revolve the nuts K K in the desired direction to raisethe eye bolts L and L thereby raising the centers of the toggles K K,which being connected at their outer ends to the inner end struts F andF act to draw their upper ends toward the center of the draw and thuscause the outer ends of the arms of the draw to be raised from theirbearings on the abutments. The draw can then be easily opened andclosed, and when it has been closed the shafto is again revolved, but inthe reverse direction, thus lowering the centers of the toggles andconsequently the ends of the draw until they again rest upon theabutments with sufficient pressure to maintain the draw in its properposition. The screw eye bolts L and L are provided at their upper endswith check nuts r and fr respectively, for the purpose of limiting thedownward movement of the eye-bolts, and consequently of the centers ofthe toggles. The general arrangement of the members forming the centralstruts or frames and the toggles is the same irrespective of the kind oftruss used for the arms of the draw. Our arrangement of the centraltoggles interposed in the upper chords of the bridge, with the nuts andscrews for operating the same, form one of the most powerful systems ofmechanism for the work in hand viz. the raising of a great weight a veryshort distance and is operated from the most convenient point, thecenter of the bridge. With this arrangement, each arm of the draw-bridgemay be made to act, when closed, as a simple bridge not only for deadweight but also for the full live load. This is eected by virtue of theoblong eyes in the inner ends of the toggle-links, which when the endsof the draw are lowered to bearings on the abutments will permit the eyebolts and toggle-pins to be lowered somewhat farther, thereby allowingsufficient play of the toggle-links on the pins to compensate for thedeflection of the arms of the draw when loaded.

The arrangement is simple, comparatively inexpensive, and the frictionis reduced to a minimum.

The bridge may be made continuous, allowing the arms to act as simplebridges for dead load and as a continuous bridge for live load, the liveload kick fora highway bridge being obviated by the action of the armsas simple bridges for dead load.

The strains for this kind of a draw-bridge would be unaffected by slightdifferences of level of its supports, (unlike the common form) since thearms adj ust themselves to the level of their supports.

What we claim as new, and desire to secure by Letters Patent of theUnited States, is

1. As a means of adjusting the ends of a drawbridge to its bearings uponthe abutments a system of toggle links forming the central portions ofthe upper chords of the trusses of said bridge in combination with screweye bolts connected to the centers of said toggles,-nuts fitted torevolve on said screws,-and suitable gears and shafting connecting saidnuts whereby said nuts may be revolved in unison to raise or lower thecenters of said toggles substantially as described.

2. In a drawbridge the combination with the trusses of the two arms ofthe bridge of a system of toggle links at each side of the bridge, eachtoggle forming the connecting link between the upper chords of thetrusses of said two arms,a triangular strut or frame at each side of thebridge over the turn-table,a screw eye bolt connected to and eX- tendingupward from the center of each toggle,a nut fitted to each of said screwbolts and supported upon the upper end of said triangular struts orframes,-gears and shafting connecting said nuts so that they may berevolved in unison,a driving shaft and suitable gears connecting thesaine to one of said nuts,-and means substantially as described forapplying power to said shafting to revolve said nuts whereby the ends ofthe bridge may be raised or lowered.

3. In a drawbridge, the combination with the trusses of the two arms ofthe bridge of a system of toggle links forming the central portions ofthe upper chords of the trusses of said bridge, a triangular strut orframe at each side of the bridge over theturn-table,-a screw threadedeye-bolt connected to and extending upward from the centerof eachtoggle,-a nut fitted to each of said screw bolts and revoluble thereon,and supported upon the upper end of said triangular strut orframe,*gears and shafting for rotatingsaid nuts in unison,- and a stopor check nut on the upper end of each of said screw eye-bolts above thegear operated nuts for limiting the downward movement of the center ofsaid toggles.

4. In a drawbridge, the combination with the trusses of the two arms ofthe bridge, of the triangular struts or frames I and I provided with thevertical guideways j j,the toggle links k k pivoted at their outer endsto the upper ends of the inner inclined struts F and F respectively ofthe arm trusses, and at their inner ends connected togethe1,the verticalscrew eyebolts L and L,-the geared nuts K and K,-the toggle pins t' andc" fitted to be movable vertically in the guideways jj and connectingthe inner ends of the toggle links and the vertical screw eye bolts,-theshafts o and 19,- and the gears m, m n, and n all constructed, arrangedand operating substantially as and for the purposes described.

5. In a drawbridge, the combination with the trusses of the two arms ofthe bridge of the toggle links 7c and 7c pivoted at their outer ends tothe upper ends of the inclined struts F and F of the arm trussesrespectively, and provided at their inner ends with eyes made oblong inthe direction of the length of said links,--the triangular struts orframes I and I,the vertical screw-eye-bolts L and L',- the toggle pinst' and t" connecting said bolts and toggle links,-the nuts K and K,-thegears m, m n and riff-and the shafts o and p, all constructed, arrangedand operating substantially as and for the purposes described.

In testimony whereot we have signed our names to this specification, inthe presence of two subscribing witnesses, on this 19th day of February,A. D. 1891.

CLAUDE A. r. TURNER. ruimr A. WARNER..

Witnesses:

N. C. LOMBARD, WALTER E. LOMBARD.

